#include "_cv.h"/*F///////////////////////////////////////////////////////////////////////////////////////// Name: cvMeanShift// Purpose: MeanShift algorithm// Context:// Parameters:// imgProb - 2D object probability distribution// windowIn - CvRect of CAMSHIFT Window intial size// numIters - If CAMSHIFT iterates this many times, stop// windowOut - Location, height and width of converged CAMSHIFT window// len - If != NULL, return equivalent len// width - If != NULL, return equivalent width// itersUsed - Returns number of iterations CAMSHIFT took to converge// Returns:// The function itself returns the area found// Notes://F*/CV_IMPL intcvMeanShift( const void* imgProb, CvRect windowIn, CvTermCriteria criteria, CvConnectedComp* comp ){ //CvMoments用来计算矩形的重心，面积等形状特征 CvMoments moments; int i = 0, eps; CvMat stub, *mat = (CvMat*)imgProb; CvMat cur_win; CvRect cur_rect = windowIn; CV_FUNCNAME( "cvMeanShift" ); //初始化跟踪窗口 if( comp ) comp->rect = windowIn; //把0阶矩和1阶矩先初始化置零 moments.m00 = moments.m10 = moments.m01 = 0; __BEGIN__; CV_CALL( mat = cvGetMat( mat, &stub )); //各种输入变量不符合要求时显示错误信息 if( CV_MAT_CN( mat->type ) > 1 ) CV_ERROR( CV_BadNumChannels, cvUnsupportedFormat ); if( windowIn.height <= 0 || windowIn.width <= 0 ) CV_ERROR( CV_StsBadArg, "Input window has non-positive sizes" ); if( windowIn.x < 0 || windowIn.x + windowIn.width > mat->cols || windowIn.y < 0 || windowIn.y + windowIn.height > mat->rows ) CV_ERROR( CV_StsBadArg, "Initial window is not inside the image ROI" ); //迭代的标准，精度=1.0，迭代次数=100 CV_CALL( criteria = cvCheckTermCriteria( criteria, 1., 100 )); //精度eps=1 eps = cvRound( criteria.epsilon * criteria.epsilon ); //最大循环次数=最大迭代次数criteria.max_iter=100 for( i = 0; i < criteria.max_iter; i++ ) { int dx, dy, nx, ny; double inv_m00; //选取搜索区域，对该矩形区域计算它的0,1阶矩 CV_CALL( cvGetSubRect( mat, &cur_win, cur_rect )); CV_CALL( cvMoments( &cur_win, &moments )); /* Calculating center of mass */ if( fabs(moments.m00) < DBL_EPSILON ) break; //搜索区域的质量m00 inv_m00 = moments.inv_sqrt_m00*moments.inv_sqrt_m00; //搜索区域的水平重心偏移dx dx = cvRound( moments.m10 * inv_m00 - windowIn.width*0.5 ); //搜索区域的垂直重心偏移dy dy = cvRound( moments.m01 * inv_m00 - windowIn.height*0.5 ); //搜索区域的重心坐标(nx,ny) nx = cur_rect.x + dx; ny = cur_rect.y + dy; //跟踪目标处于图像边缘时进行一些相应的处理 if( nx < 0 ) nx = 0; else if( nx + cur_rect.width > mat->cols ) nx = mat->cols - cur_rect.width; if( ny < 0 ) ny = 0; else if( ny + cur_rect.height > mat->rows ) ny = mat->rows - cur_rect.height; dx = nx - cur_rect.x; dy = ny - cur_rect.y; cur_rect.x = nx; cur_rect.y = ny; /* Check for coverage centers mass & window */ //精度达到要求时即可退出循环 if( dx*dx + dy*dy < eps ) break; } __END__; //对meanshift函数的返回值赋值 //comp->rect是收敛后窗口位置，comp->area是最终窗口中所有像素点的和 if( comp ) { comp->rect = cur_rect; comp->area = (float)moments.m00; } return i;}/*F///////////////////////////////////////////////////////////////////////////////////////// Name: cvCamShift// Purpose: CAMSHIFT algorithm// Context:// Parameters:// imgProb - 2D object probability distribution// windowIn - CvRect of CAMSHIFT Window intial size// criteria - criteria of stop finding window// windowOut - Location, height and width of converged CAMSHIFT window// orientation - If != NULL, return distribution orientation// len - If != NULL, return equivalent len// width - If != NULL, return equivalent width// area - sum of all elements in result window// itersUsed - Returns number of iterations CAMSHIFT took to converge// Returns:// The function itself returns the area found// Notes://F*/CV_IMPL intcvCamShift( const void* imgProb, CvRect windowIn, CvTermCriteria criteria, CvConnectedComp* _comp, CvBox2D* box ){ const int TOLERANCE = 10; CvMoments moments; double m00 = 0, m10, m01, mu20, mu11, mu02, inv_m00; double a, b, c, xc, yc; double rotate_a, rotate_c; double theta = 0, square; double cs, sn; double length = 0, width = 0; int itersUsed = 0; CvConnectedComp comp; CvMat cur_win, stub, *mat = (CvMat*)imgProb; CV_FUNCNAME( "cvCamShift" ); comp.rect = windowIn; __BEGIN__; CV_CALL( mat = cvGetMat( mat, &stub )); //调用cvMeanShift函数 CV_CALL( itersUsed = cvMeanShift( mat, windowIn, criteria, &comp )); windowIn = comp.rect; //对边界情况进行处理 windowIn.x -= TOLERANCE; if( windowIn.x < 0 ) windowIn.x = 0; windowIn.y -= TOLERANCE; if( windowIn.y < 0 ) windowIn.y = 0; windowIn.width += 2 * TOLERANCE; if( windowIn.x + windowIn.width > mat->width ) windowIn.width = mat->width - windowIn.x; windowIn.height += 2 * TOLERANCE; if( windowIn.y + windowIn.height > mat->height ) windowIn.height = mat->height - windowIn.y; CV_CALL( cvGetSubRect( mat, &cur_win, windowIn )); /* Calculating moments in new center mass */ //计算新中心处的颜色统计矩 CV_CALL( cvMoments( &cur_win, &moments )); m00 = moments.m00; //0阶 m10 = moments.m10; //水平1阶 m01 = moments.m01; //垂直1阶 mu11 = moments.mu11; //水平垂直2阶 mu20 = moments.mu20; //水平2阶 mu02 = moments.mu02; //垂直2阶 //目标矩形的质量太小了就退出 if( fabs(m00) < DBL_EPSILON ) EXIT; //质量的倒数，只是为了下面计算方便，可以把除法表示成乘法 inv_m00 = 1. / m00; xc = cvRound( m10 * inv_m00 + windowIn.x ); yc = cvRound( m01 * inv_m00 + windowIn.y ); a = mu20 * inv_m00; b = mu11 * inv_m00; c = mu02 * inv_m00; /* Calculating width & height */ square = sqrt( 4 * b * b + (a - c) * (a - c) ); /* Calculating orientation */ //计算目标主轴方向角度 theta = atan2( 2 * b, a - c + square ); /* Calculating width & length of figure */ cs = cos( theta ); sn = sin( theta ); rotate_a = cs * cs * mu20 + 2 * cs * sn * mu11 + sn * sn * mu02; rotate_c = sn * sn * mu20 - 2 * cs * sn * mu11 + cs * cs * mu02; //下次搜索窗口的长宽 length = sqrt( rotate_a * inv_m00 ) * 4; width = sqrt( rotate_c * inv_m00 ) * 4; /* In case, when theta is 0 or 1.57... the Length & Width may be exchanged */ if( length < width ) { double t; CV_SWAP( length, width, t ); CV_SWAP( cs, sn, t ); theta = CV_PI*0.5 - theta; } /* Saving results */ if( _comp || box ) { int t0, t1; int _xc = cvRound( xc ); int _yc = cvRound( yc ); t0 = cvRound( fabs( length * cs )); t1 = cvRound( fabs( width * sn )); t0 = MAX( t0, t1 ) + 2; comp.rect.width = MIN( t0, (mat->width - _xc) * 2 ); t0 = cvRound( fabs( length * sn )); t1 = cvRound( fabs( width * cs )); t0 = MAX( t0, t1 ) + 2; comp.rect.height = MIN( t0, (mat->height - _yc) * 2 ); comp.rect.x = MAX( 0, _xc - comp.rect.width / 2 ); comp.rect.y = MAX( 0, _yc - comp.rect.height / 2 ); comp.rect.width = MIN( mat->width - comp.rect.x, comp.rect.width ); comp.rect.height = MIN( mat->height - comp.rect.y, comp.rect.height ); comp.area = (float) m00; } __END__; if( _comp ) *_comp = comp; if( box ) { box->size.height = (float)length; box->size.width = (float)width; box->angle = (float)(theta*180./CV_PI); box->center = cvPoint2D32f( comp.rect.x + comp.rect.width*0.5f, comp.rect.y + comp.rect.height*0.5f); } return itersUsed;}/* End of file. */
